// Copyright 2011, University of Freiburg,
// Chair of Algorithms and Data Structures,
// Author: Hannah Bast <bast>.

#include <iostream>

// This program calculates the area of a circule.
using std::cout;
using std::cin;
using std::endl;

const float pi = 3.141592654;

int main()
{
        float radius;

        cout << "Enter the radius: ";
        cin  >>  radius;

        cout << "Area of the circule with radius " << radius << " is ";
        cout << pi * radius * radius << endl;

        return 0;
}
